Anthrax

What is anthrax?

Anthrax is an acute infectious disease caused by the
spore-forming bacterium Bacillus anthracis. Anthrax most commonly occurs
in wild and domestic animals like cattle, sheep, goats, camels and antelopes.
It also can occur in humans when they are exposed to infected animals or tissue
from infected animals, or following an intentional release of anthrax spores as
an agent of biological war or terrorism.

How common is anthrax and who
can get it?

Until the bioterrorism attacks in the U.S. in 2001, the
last reported case of inhalation anthrax was in 1976; the last reported case of
cutaneous anthrax, which is more common, occurred in 2000. Illinois most
recent case was in 1960. Anthrax occurs in animals, most commonly in
agricultural regions including Africa, Asia, the Caribbean, Central and South
America, southern and eastern Europe, and the Middle East. Anthrax in livestock
does occur infrequently in the United States. When anthrax affects humans, it
is usually due to an occupational or recreational exposure to infected animals
or their products. Workers who are exposed to dead animals and to animal
products from other countries where anthrax is more common may become infected
with Bacillus anthracis.

How is anthrax
transmitted?

People were infected with anthrax during the 2001
bioterrorism attacks by inhaling thousands of airborne spores or by touching a
powder form that was contained in letters delivered by the U.S. Postal Service.
Inhalation anthrax occurs when the tiny spores are breathed in and settle in
the lung, while cutaneous (skin) anthrax occurs when spores enter the body
through minor cuts or abrasions on the skin. Humans also can become infected
with anthrax by handling products from infected animals, by inhaling anthrax
spores from contaminated animal products or by eating undercooked meat from
infected animals.

What are the symptoms of
anthrax?

Symptoms of disease vary depending on how the disease was
contracted, but usually occur within seven days.

Cutaneous. Most cases occur when the bacterium
enters through a cut or abrasion on the skin. The infection develops one to 12
days after exposure and begins as a raised itchy bump that resembles an insect
bite. Within one to two days, it becomes a fluid-filled blister and then a
painless ulcer, usually 1 cm-3 cm in diameter, with a characteristic black,
dying area in the center. Patients may have fever, malaise and headache, and
lymph glands in the area near the ulcer may swell. About 20 percent of
untreated cases result in death, although deaths are rare when antibiotic
treatment is provided.

Inhalation. This is the most lethal form of
anthrax. While the incubation period in humans is unclear, it is believed to
range from one to seven days, but possibly up to 60 days. Initial symptoms may
resemble an influenza-like illness with sore throat, mild fever, muscle aches
and fatigue. These symptoms may progress to severe breathing problems and
shock, with meningitis frequently developing. After the onset of symptoms,
inhalation anthrax is fatal in 75 percent of the cases, even with all possible
care. Early antibiotic treatment increases chances for survival.

Intestinal. The intestinal disease form of anthrax
usually follows the consumption of raw or undercooked contaminated meat and has
an incubation period of one to seven days. It is characterized by an acute
inflammation of the intestinal tract. Initial signs of nausea, loss of
appetite, vomiting and fever are followed by abdominal pain, vomiting of blood
and severe, often bloody, diarrhea. It also can cause lesions at the base of
the tongue, sore throat, difficulty swallowing, fever and swelling near lymph
nodes. Death occurs in 25 percent to 60 percent of cases.

Is there a test to determine if I have been exposed to
anthrax?

There is no screening test for anthrax. There is no test
a doctor can perform that says you have been exposed or carry the bacteria. The
only way exposure can be determined is through a public health investigation.
The tests that you hear or read about, such as nasal swabs and environmental
tests, are not tests to determine whether an individual should be treated.
These kinds of tests are used only to determine the extent of exposure in a
given building or workplace.

Can anthrax be spread from person to
person?

No. Anthrax is not contagious and cannot be transmitted
from person to person.

How is anthrax
diagnosed?

Anthrax is diagnosed by culturing Bacillus
anthracis from blood, skin lesions or respiratory secretions or by
measuring specific antibodies in the blood of persons with suspected
cases.

How can I detect the presence of
anthrax?

Bacillus anthracis spores do not have a
characteristic appearance, smell or taste. Spores themselves are too small to
be seen by the naked eye, but have been mixed with powder to transport them.
Anthrax can only be identified through sophisticated laboratory testing.

Is there a treatment for
anthrax?

Doctors can prescribe several antibiotics. To be
effective, treatment should be initiated early. If left untreated, the disease
can be fatal.

When there has been a known bioterrorist exposure to
B. anthracis, certain persons who had contact with the infectious
material will be recommended for preventive treatment based on an individual
risk assessment performed by public health officials. Determination of exposure
will be made after police and public health investigative work and not by
testing individuals. Results of nasal culture should not be used as a basis for
prophylaxis. Positive nasal cultures confirm exposure but not the presence of
disease. Negative cultures do not rule out exposure.

Is there a way to prevent
exposure?

While it is not possible to totally eliminate the threat
of a bioterrorism attack, the risk to the general public is low and can be
further reduced by being alert for suspicious packages and by handwashing after
opening the mail. Heightened public health surveillance continues so that
anthrax cases can be promptly recognized and treated.

Can you get anthrax from contaminated
mail?

As evidenced in 2001 in various cities on the East Coast,
yes, it is possible and people should be alert for suspicious mail.

Mail might be considered suspicious if it includes the
following:

Inappropriate or unusual
labeling

Excessive postage

Handwritten or poorly typed addresses

Misspellings of common words

Strange return address or no return address

Incorrect titles or title without a name

Not addressed to a specific person

Marked with restrictions such as Personal,
Confidential or Do not X-ray

Marked with any threatening language

Postmarked in a city or state that does not match the
return address

Appearance

Powdery substance can be felt through or appears on the
package or envelope

Oily stains, discolorations or odor

Lopsided or uneven envelope

Excessive packaging material such as masking tape,
string, etc.

Other suspicious signs

Excessive weight

Ticking sounds

Protruding wires or aluminum foil

What should you do if you
receive suspicious mail?

Do not shake or empty the contents.

Do not carry the package or envelope, show it to others
or allow others to examine it.

Put the package or envelope on a stable surface. If any
contents have spilled, do not sniff, touch, taste or look closely at it.

Alert others in the area. Leave the area, close any
doors and take actions to prevent others from entering the area. If possible,
shut off the ventilation system.

Wash hands with soap and water to prevent spreading
potentially infectious material to face or other areas of the skin. Seek
additional instructions for exposed or potentially exposed persons.

If at work, notify a supervisor, a security officer or
law enforcement official. If at home, contact the local law enforcement
agency.

If possible, create a list of persons who were in the
room or area when the suspicious letter or package was recognized and a list of
persons who may have handled the letter or package. Give the lists to both the
local public health authorities and law enforcement officials.

Persons at greater risk, such as a postal worker or
mailroom clerk, should wear protective gloves and possibly a mask. Anyone who
handles suspicious mail should thoroughly wash his/her hands.

What is the anthrax
vaccine?

A vaccine has been developed for anthrax that protects
against invasive disease, but it is currently only recommended for persons at
high risk of exposure and is not available commercially. The vaccine has been
mandated for U.S. military personnel between the ages of 18 and 65 (all are to
be vaccinated by 2005). It is recommended for laboratory personnel who work
directly with the organism and persons who handle imported animal hides and
furs or potentially infected animal products in high incidence areas (not the
U.S.).